title: Mechanism of autoimmune hepatic fibrogenesis induced by an adenovirus encoding the human liver autoantigen cytochrome P450 2D6.
abstract: Autoimmune hepatitis type 2 (AIH-2) is a severe autoimmune liver disease with unknown etiology. We recently developed the CYP2D6 mouse model for AIH-2, in which mice are challenged with an adenovirus (Ad-2D6) expressing human cytochrome P450 2D6 (hCYP2D6), the major autoantigen in AIH-2. Such mice develop chronic hepatitis with cellular infiltrations and generation of hCYP2D6-specific antibodies and T cells. Importantly, the CYP2D6 model represents the only model displaying chronic fibrosis allowing for a detailed investigation of the mechanisms of chronic autoimmune-mediated liver fibrogenesis. We found that hCYP2D6-dependent chronic activation of hepatic stellate cells (HSC) resulted in an increased extracellular matrix deposition and elevated expression of α-smooth muscle actin predominantly in and underneath the liver capsule. The route of Ad-2D6 infection dramatically influenced the activation and trafficking of inflammatory monocytes, NK cells and hCYP2D6-specific T cells. Intraperitoneal Ad-2D6 infection caused subcapsular fibrosis and persistent clustering of inflammatory monocytes. In contrast, intravenous infection caused an accumulation of hCYP2D6-specific CD4 T cells throughout the liver parenchyma and induced a strong NK cell response preventing chronic HSC activation and fibrosis. In summary, we found that the location of the initial site of inflammation and autoantigen expression caused a differential cellular trafficking and activation and thereby determined the outcome of AIH-2-like hepatic damage and fibrosis.
authors.affiliation: Pharmazentrum Frankfurt/ZAFES, Johann Wolfgang Goethe University, Frankfurt am Main, Germany.
authors.forename: Edith
authors.initials: E
authors.lastname: Hintermann
authors.forename: Janine
authors.initials: J
authors.lastname: Ehser
authors.forename: Monika
authors.initials: M
authors.lastname: Bayer
authors.forename: Josef M
authors.initials: JM
authors.lastname: Pfeilschifter
authors.forename: Urs
authors.initials: U
authors.lastname: Christen
mesh_terms: D000199:Actins / Q000276:immunology; D000256:Adenoviridae / Q000276:immunology*; D000257:Adenoviridae Infections / Q000276:immunology*; D000818:Animals; D001324:Autoantigens / Q000276:immunology*; D001402:B-Lymphocytes / Q000276:immunology; D015496:CD4-Positive T-Lymphocytes / Q000276:immunology; D002478:Cells, Cultured; D019389:Cytochrome P-450 CYP2D6 / Q000276:immunology*; D005355:Fibrosis / Q000276:immunology; D055166:Hepatic Stellate Cells / Q000276:immunology; D019693:Hepatitis, Autoimmune / Q000276:immunology*; D006801:Humans; D007249:Inflammation / Q000276:immunology; D007694:Killer Cells, Natural / Q000276:immunology; D008099:Liver / Q000276:immunology*; D008107:Liver Diseases / Q000276:immunology; D051379:Mice; D009000:Monocytes / Q000276:immunology
chemical_list: C541116:ACTA2 protein, human; D000199:Actins; D001324:Autoantigens; D019389:Cytochrome P-450 CYP2D6
keywords: AIH; Ad; Adenoviral vectors; Autoimmune hepatitis; CCl(4); CYP2D6; Cytochrome P450; ECM; Fibrosis; HSC; LKM-1; Liver immunology; PBC; PSC; adenovirus; autoimmune hepatitis; carbon tetrachloride; extracellular matrix; hepatic stellate cell; human Cytochrome P450 2D6; liver-kidney-microsomal type 1; primary biliary cirrhosis; primary sclerosing cholangitis; α-smooth muscle actin; αSMA